<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
        "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
    <meta content="This is Chris's Home Page" name="description">
    <meta content="Chris,Web,Music,photo" name="keywords">
    <meta content="text/html;charset=utf-8" http-equiv="content-type"/>
    <title>Hello JavaScript!</title>
    <script type="text/javascript">

        function add(a, b) {
            return a + b;
        }

        function sub(a, b) {
            return a - b;
        }

        function cacu(a, b, op) {
            return op(a, b);
        }

        alert(cacu(50, 30, sub));

    </script>
</head>
<body>
<br/>
<br/>
<br/>
<br/>
<button>Click me</button>
</body>
</html>
